The present invention relates to semiconductor electronics, and more specifically, to graphene field-effect transistors.
Graphene exhibits exceptional electronic properties such as a relative high carrier mobility and transconductance. These exceptional properties enable graphene to be used to form graphene field-effect transistors (GFETs), which may be useful in applications up to the terahertz frequency region. A typical GFET includes a source contact and a drain contact with a graphene sheet extending between them to form a gated channel. The GFET operates, in part, by modulating the conductance of the graphene sheet, usually via a gate contact metal proximate the graphene sheet. One of the leading challenges in GFET technology is that the intrinsic properties of the graphene are substantially compromised at the interfaces of the GFET, i.e., metal source/drain contacts, gate dielectrics, supporting substrates, etc. These interfaces produce sizable contact resistance, reduced carrier mobility due to scattering centers, and many other hindrances.